[clang] [flang] [llvm] [InstCombine] Canonicalize constant GEPs to i8 source element type (PR #68882)

[Florian Hahn via cfe-commits]

https://github.com/fhahn approved this pull request.

LGTM, looks like a great first step! Will be interesting to see what kind of regressions this surfaces (if any)

https://github.com/llvm/llvm-project/pull/68882